oracle trigger pl sql - sql

Question

I have a database user that contains four tables department, employee, address and contact info, then stored 5 Records in each table, and wrote the PL/SQL Statement for the following:
Stored a record into employee, address and contact using trigger.
the insert into view is not working ! it results in error ? can you guys help me with this ?
this is my code :
-- Create Tables :
CREATE TABLE address (
code int primary key,
city varchar2(30),
street varchar2(30)
);
create table Department (
DepId int primary key ,
Dep_Name varchar2(30) ,
Dep_adress varchar(30));
create table Employee (
Emp_Id int primary key ,
firstName varchar2(30),
lastName varchar2(30),
salary int,
Dep_Id int references Department (DepId),
Code int references address (code));
CREATE TABLE contact_info (
email varchar2(30) primary key ,
phone int ,
EmpId int references Employee (Emp_Id));
-- insert :
insert into Department values (1,'IT','Amman');
insert into Department values (2,'CS','Jerash');
insert into Department values (3,'accounting','Amman');
insert into Department values (4,'managment','Amman');
insert into Department values (5,'employment','Amman');
insert into address values (50,'Amman','AAA');
insert into address values (60,'Amman','AAB');
insert into address values (70,'Amman','AAC');
insert into address values (80,'Jerash','AAD');
insert into address values (90,'Irbid','AAE');
insert into Employee (Emp_Id,firstName,lastName,salary,Dep_Id,Code) values (1,'john' , 'samo' , 1000 , (select DepId from Department where Dep_Name = 'IT'),(select code from address where street = 'AAA'));
insert into Employee (Emp_Id,firstName,lastName,salary,Dep_Id,Code) values (2,'mark' , 'wol' , 2000 , (select DepId from Department where Dep_Name = 'IT'),(select code from address where street = 'AAB'));
insert into Employee (Emp_Id,firstName,lastName,salary,Dep_Id,Code) values (3,'ahmad' , 'moh' , 1100 , (select DepId from Department where Dep_Name = 'IT'),(select code from address where street = 'AAC'));
insert into Employee (Emp_Id,firstName,lastName,salary,Dep_Id,Code) values (4,'maher' , 'imk' , 1700 , (select DepId from Department where Dep_Name = 'CS'),(select code from address where street = 'AAD'));
insert into Employee (Emp_Id,firstName,lastName,salary,Dep_Id,Code) values (5,'ali' , 'geh' , 1200 , (select DepId from Department where Dep_Name = 'CS'),(select code from address where street = 'AAE'));
insert into contact_info values ('john#gmail.com',0785602200, (select Emp_Id from Employee where salary = 1000));
insert into contact_info values ('mark#gmail.com',0785602201, (select Emp_Id from Employee where salary = 2000));
insert into contact_info values ('ahmad#gmail.com',0785602202, (select Emp_Id from Employee where salary = 1100));
insert into contact_info values ('maher#gmail.com',0785602203, (select Emp_Id from Employee where salary = 1700));
insert into contact_info values ('ali#gmail.com',0785602204, (select Emp_Id from Employee where salary = 1200));
-- trigger :
CREATE VIEW vw_address1 AS
SELECT
code,
city,
street
FROM
address;
CREATE OR REPLACE TRIGGER new_trg2
INSTEAD OF INSERT ON vw_address1
FOR EACH ROW
DECLARE
l_code NUMBER;
BEGIN
-- insert a new address first
INSERT INTO address(code,city, street)
VALUES(:NEW.code,:NEW.city, :NEW.street)
RETURNING code INTO l_code;
END;
insert into vw_address1(code,city,street) values (2,'Amman','AAB');